Ensuring shale gas projects for Poland and beyond
Hydraulic fracturing, sometimes known as fracking, is a well-established process for improving fluid flow through rocks. However, it has become controversial largely as a result of the rapid expansion of the shale gas industry in the USA, where light-touch regulation and limited understanding of the subsurface risks led to several high-profile environmental incidents. Some EU countries, including France and Bulgaria, have banned fracking as a result of these incidents and the associated concerns of the public. RSK has been involved in the SHEER project (SHale gas Exploration and Exploitation induced Risks), an EU-funded Horizon 2020 research project, which was established to provide a formal research platform investigating the risks and benefits associated with shale gas extraction.
Fracking involves pumping water, sand and chemicals at high pressure into boreholes to open up fissures in the rock. It is widely used in the conventional oil and gas industry and in water wells for improving well yields but is best known these days in the context of shale gas production. This process involves drilling long horizontal wells in shale rocks deep underground, where the fissures produced by hydraulic fracturing enable the natural gas to flow back up the well.
SHEER’s key aims included assisting in developing best practices for assessing and mitigating the environmental footprint of natural gas developments. The research centred on groundwater contamination, air pollution, induced seismicity, public perception, information sharing and cost–benefit analysis. Working in partnership with the University of Glasgow, UK, RSK led the groundwater research and cost–benefit studies. These included reviewing the risks to groundwater from shale oil and gas operations, developing generic risk settings, studying an aquifer adjacent to an operational site and developing recommendations and best practices.
RSK’s initial work involved reviewing the shale basins within the EU to identify their resource potential for shale oil and gas, and the potential risks regarding groundwater extraction as a drinking water resource. Our screening exercise, done for each basin, identified their main characteristics, and we extended the process so that it could be applied to other basins or parts of basins that may become future fracking locations.
A Polish research team identified a shale gas exploration site in the Stara Kiszewa concession area in Pomerania, northern Poland. The aquifer study required groundwater monitoring boreholes, so RSK helped to select suitable sites for four locations near the shale-gas well. Baseline monitoring lasted until hydraulic fracturing began; monitoring continued for 18 months after the fracking operations. Throughout this period, we assessed the groundwater levels and chemistry, and collected dissolved gas data.
Using the site’s geological, hydrogeological and hydrological data, RSK built updated geological and hydrogeological models for the area and developed a full, conceptual site model. The data also enabled the development of a set of baseline characteristics against which to compare post-fracturing data to determine if there had been any changes. The RSK team also extensively reviewed cases of groundwater contamination attributed to shale oil and gas operations. With the site results and the analysis, this review enabled RSK and the University of Glasgow to propose key recommendations for best practice in future shale oil and gas operations in the EU; these particularly relate to establishing baseline conditions. The recommendations form a major project output and will inform industry best practices and future research in this field.